1. Field of the Invention
This invention relates to carts that preferably inter-fit with one another and are provided with features to facilitate the unloading thereof or otherwise assist in transferring items deposited therein without undue physical strain.
2. Description of the Prior Art
Wheeled shopping carts are made available in grocery stores, department stores, home improvement stores, and the like for the convenience of their customers to accommodate the transportation of items purchased to a check-out counter and/or to their vehicle. Thus, shopping carts of the general type being considered herein are well known. Invariably, shopping carts have a basket for holding user-selected items. Typically, the basket is mounted on a frame that has a handle and four caster-type wheels. In addition, shopping carts are usually nestable or stackable within one another to minimize storage space.
However, many users find the depth of the shopping cart basket to be very inconvenient because reaching items placed on the floor of the shopping cart basket requires the user to reach or bend down. Such bending movement may be painful or even difficult for certain users of a typical shopping cart. Thus, there is a need for shopping carts adapted to facilitate the retrieving of the contents therein without having a user to reach or bend down into the shopping cart basket.
Previous shopping carts with telescoping or movable baskets were intended to increase the size of the shopping cart basket in proportion to the quantity and/or weight of the items in the shopping cart basket. For example, U.S. Pat. No. 2,958,536 to F. W. Young discloses a telescoping grocery cart having means for increasing the lading (i.e., loading) capacity thereof. For another example, U.S. Pat. No. 3,787,063 to Oliver discloses a shopping cart or the like having a movable bottom wall displaceable between retracted and extended positions in accordance with the magnitude of the weight supported by the bottom wall. In addition, U.S. patent application Ser. No. 2002/0135145 to Saccani discloses a shopping cart with the ability to move in response to downward force.
However, all these previous shopping carts provide that the bottom wall of the shopping cart basket is initially or permanently set at a typical depth from the top of the sidewalls. In other words, previous shopping carts required that a user reach or bend down to reach and/or retrieve items placed on the bottom wall of the cart.
U.S. Pat. No. 5,863,054 to Flores describes a grocery cart platform lift, which is a vertically movable horizontal shelf that is normally positioned near the upper rim of the basket of the cart. The shelf is spring biased and as it becomes loaded, the shelf tends to move downwardly within the shopping cart basket. As the shelf is unloaded, it tends to move upwardly, thereby making it easier to unload the remaining items in the shopping cart. However, the shelf is mounted only to the front wall of the shopping cart basket by a pair of telescoping tracks. Each track has a single spring biasing the shelf in the upward position.
Providing a shopping cart with a short vertically movable shelf biased in the upward direction by a single pair of springs is an incomplete solution to problem. If the springs are highly elastic to allow quick lowering of the bottom wall, the springs can be easily over-loaded such that a number of items must first be removed from the shopping cart basket before the bottom wall will begin to rise. If the springs are only slightly elastic to allow quick rising of the bottom wall, the springs will inconveniently limit the available volume of the shopping cart basket unless several heavy items are loaded onto the bottom wall.
Inadequate biasing means for resiliently supporting a mass of a load is not the only problem associated with many of the known cart structures. Loading a cart is typically done without consideration of torsional or bending forces generated by a load. It is not unusual to see a cart overloaded with numerous shopping items that may be unevenly distributed within the basket or receptacle of the cart. As a consequence, loading and steering the cart are rather difficult due to the action of the torsional forces directed along different planes and tend to prevent both moving the cart along a relatively linear path and along an arcuate path, if a need exists. Furthermore, under certain circumstances, the overloaded cart may tip over on either of its sides due to uneven distribution of the weight inside the cart. In summary, many of the known cart structures may not be adequately configured to withstand torsional or bending moments generated by the load being transported.
A need, therefore, exists for a shopping cart that reduces the need for a user to bend while loading and unloading the basket.
Another need exists for a shopping cart that has a receptacle with a bottom wall movable in response to loading or unloading the receptacle.
Further, a need exists for a shopping cart that has a structure capable of withstanding lateral, torsional or bending forces typically generated by the load being transported.